Drawbar actuating power amplifying apparatus



Sept. 8, 1953 H. M. OLSON 2,651,207 I DRAWBAR ACTUATING POWER AMPLIFYING APPARATUS Filed July 10, 1950 2 Sheets-Sheet 1 m HOLLY M. OLSQN Fi i W .llllll Q V ATTORNEYS x,

p 1953 H. M. OLSON DRAWBAR ACTUATING POWER AM PLIFYING APPARATUS 2 Sheets-Sheet 2 Filed July 10, 1950 m w N E V I N O s L O M Y L L 0 HH womsvs has previously been used in Patented Sept. 8, 1953 DRAWBAR' ACTUATING POWER AMPLI- FYING APPARATUS Holly M. Olson,

Muskegon, Mich, a'sslgnor to Sealed Power Corporation, corporation of Michigan Muskegon, Mich, a.

Application July 10, 1950; Serial No. 172,978 3 Claims. (01. 74 l) The present invention relates to a power amphfying unit, including a cylinder, a piston therein movable by fluid pressure in opposite directions in the cylinder, and a draw bar operatively associated with the piston and extending through one end of the cylinder, between which draw bar and the piston a very simple, practical and novel means for multiplying the force of pull of the draw bar is accomplished, upon the principle of a wedge or inclined plane, which is also the principle of the screw, so that while the piston moves a distance in the cylinder, the draw bar moves a fractional part of such distance, with the result of greatly increasing the force which the draw bar applies to hold an article or series of articles clamped securely in position for machining.

My invention has been used, primarily, in the outside finishing of piston rings, but may also be used in many other machinings, such as cylinders, or the like, the Work, namely, the piston rings or the cylinders, rotating at high speed, being clamped releasably in the use of my invention against slipping or other undesired movement, the clamping and release taking place substantially instantaneously. With my invention a perfect balance, free from vibration at all speeds, is obtained, the amount of consumption of compressed air or other fluid pressure is at a minimum, clam ing and release is accomplished instantly, the structure is simple and relatively inexpensive to produce, backlash or lost motion is eliminated, the inertia factor is very low, and a clamping action is developed in which the power approaches that of a screw and a nut tightened by a wrench, which means of clamping articles,

like piston rings, cylinders and the like which are to be outside turned, ground or otherwise finished,

a large measure.

An understanding of the invention may be had from the following description, taken in connection with the accompanying drawings, in which Fig. 1 illustrates a turning lathe having my invention applied thereto.

Fig. 2 is a fragmentary enlarged elevation illustrative of the clamping mechanism, fluid operated and in which the plied, showing a series of piston rings clamped in position to be machine finished at their outer curved surfaces.

Fig. 3 is a longitudinal vertical section through the apparatus embodying my invention, substantially on the plane of line 3-3 of Fig. 4, and

Figs. 4 and 5 are transverse vertical sections, substantially on the planes of lines 4-4 and 5 5 respectively of Fig, 3, looking in the direction indicated. Y

clamping power is multi-' 2 Like reference characters refer to like parts in the different figures of the drawings.

In the structure illustrated (Fig. 3), a cylinder has an end I integral with walls 2 extending rod 3, having an enlarged head within the cylinder extends. The rod has two longitudinal pasvalve l0 (Fig. 1), conveniently located for the lathe operator to reverse the flow of compressed air, and thus reverse the direction of movement of the piston, hereafter described, within the cylinder.

of the cylinder, the member l 2 is slotted diametrically as at I 4. Centrally of the piston part l2 and between the opposite slots I4 a member I5 is located, being mounted for rocking movement on a heavy pin l6 extending through it and through the piston part l2. The member It: has opposed shoulders at the inner ends of movement of the draw mounted at each of the slots 19. One arm of the bell crank lever extends into each of the slots H and opposed slots in wedge member l5 and at its free end is provided with a pair of rollers 2 I. Such rollers may ride upon the inclined sides or edges; H. or the wedging member ii. The other arms. of the bell crank lever extend toward each other and slightly overlap substantially at the center of the cylinder (Fig. 5).

A draw bar 22 passes through the at its inner end is formed with a outer head 23, spaced apart sides 24 and an inner cross head 25 against the outer. sideoi which the,

head [8 and ends of last mentioned arms of. the; bell crank;

levers bear.

It is apparent that when compressed air. or other equivalent fluid pressure flows through the conduit 8 and passages 5 and 6 the piston will be moved to the left (Fig. 3). The rollers 2| will ride upon the diverging sides or edges or the wedgin member l5, swinging the horizontal and longer arms of the bell. crank levers 2.0 away from each other, and moving the short arms against theahead 25' so as to-movethe draw bar 22 lengthwise tothe left. On reverse flow of the pressure fluid through the conduit 8, and thence through the passage 4, the piston will bemoved in the opposite direction and the cross head 25 will be pressed. against by the outer end of the wedging member to positively move the draw bar 22 longitudinally in the opposite. direction.

The power amplifying cylinder apparatus may be used. as an accessory to a turning lathe, as shown in Fig. 1, being mounted at the outer end of. the head stock spindle with the draw bar passing through such spindle, which will be hollow, and have an axial opening therethrough for such passage. At the outer end of the draw bar, which will have a head at such end, a collar 26 is used to press against the outermost or a plurality or series of piston rings 21 and clamp them against the hollow spindle 28 upon the longitudinal bar 22 to the left.

The distance that the draw bar is moved 1ongitudinally is short. Initially upon the rollers 22 passing over the shoulders at the inner ends of the inclined sides H of the wedging member t5, there will be a greater rapidity of movement of thedraw bar than after the rollers reach such inclined sides H. This causes the collar 26 to quickly come against the outermost piston ring 21 and, thereafter, the movement will be. slower until collar 26 can be moved no farther but will be: subjected to static fluid pressure between the head t8 and the piston. Under such conditions the piston rings 21 are held securely clamped until a reversal of the flow of the pressure fluid, by operation of the manually controlled valve it], takes place.

While the invention has been shown as used in conjunction with clamping a plurality of pistogether during outside machining operation ton rings to maintain them securely clamped thereon, it is apparent that many other articles.-

such ascylinders or forms of cylindrical outline may beclamped for machining in the same manner.

With the present invention the bell crank levers are synchronized in their movements, the wedging member 15 having a rocking mounting upon the pin it, so that. the wedging member is "fioatingly mounted and automatically conforms to. the rollers on. the bell crank levers to operate them simultaneously and. in equal amounts. The

power is: applied evenly to: each fulcrum; or; the

yoke, having an bell crank levers and insures against any tendency of the piston to cant or tilt in the cylinder. It is of course apparent that the inclined surfaces of the wedge member 15 may be varied to increase or decrease the power mutliplication and, as shown,;theshoulders provided: by cutting away the inner-end corners of the wedging member at opposite sides provides for a more rapid movement of the bell crank levers at the beginning of a clamping stroke.

Th structure described is one which may take the place of a direct acting piston and cylinder clamping means, with a very great reduction in the. size oi: the,- cylinder and its weight. The clamping iorce which may be applied with a cylinder approximately four inches in diameter will equal that of a direct acting piston cylinder apparatus of three to four times such diameter. The inertia of the moving parts is small so that rapid starting andstopping. is attained with instant clamping and instant release. The structure embodying the invention is simple, practical, very sturdy and dependable. The cylinder rotates with the lathe spindle while the air supplying housing I is stationary. Vibration at. all speeds is substantially non-existent. The consumption of compressed air isreduced to a minimum.

The invention is defined in the appended claims and is to be considered. comprehensive of all forms of structure coming within their scope.

I claim:

1. Apparatus comprising, a. fixed. support, a draw bar slidably passing through the support, a yoke connected to-the draw bar at an end thereof, a second support, means for mounting the second support for movements in opposite directions toward and away from the yoke, a wedging member having oppositely inclined sides diverging :irom eachother toward the fixed support, said yoke being positioned between the wedging member and said fixed support, bell crank levers pivotally mounted on the fixed support at opposite inclined sides oi the wedging member, engaging each at one end with the adjacent inclined side of said wedging member, and having arms at their opposite ends extending toward each other, said yoke having a head transverse to the length of the draw bar with which said arms engage, and means for mounting said wedging member on the movable second support for rocking movement about an axis perpendicular to the longitudinal axis of the draw bar.

2'. Apparatus comprising, a fixed support, a draw bar slidably passing through the support, a yoke connected to the draw bar at an end thereof, a second support, means for mounting the second support for movements in opposite directions toward and away from the yoke, a wedging member having oppositely inclined sides diverging from its inclined sides converge having recesses at opposite sides, said rollers being received in said recess when in conjunction therewith, the other arms of said bell crank levers extending toward each other, said yoke having, a head transverse to the draw bar with which said last mentioned arms engage, and means for mounting saidwedging member on the movable second support for toward said end of the fixed support, said wedging rocking movement about an axis perpendicular to member at inclined opposite sides thereof having the longitudinal axis of the draw bar. slots in which said second mentioned arms of the fixed support, a yoke connected to the draw bar of said bell crank levers for bearing against adjaadjacent said end of the fixed support comprising, cent inclined sides of the wedging members. spaced sides extending away from the draw bar HOLLY M. OLSON.

with an opening between the cross head and the 10 References Cited the fi Of this Pate t adjacent end of the draw bar, a second support UNITED STATES PATENTS movably mounted on the fixed support for move- Number Na D t ment toward and away from said end of the fixed 728 572 M e1903 support in a direction parallel to the length of the 900856 Jecklm O 13 1908 draw bar, two bell crank levers pivotally mounted l5 c 1,334,503 Olson Mar. 23, 1920 on the fixed support at opposite sides of and 2,134,227 Forkhardt Oct. 25, 1938 spaced from the longitudmal axis of the draw 2 444 260 Kene J 29 1948 bar, each having one arm extending into the yoke 2460251 Dia y 1949 opening and engaging said cross head and each 2539913 6 1951 having a second arm generally parallel to the 20 p length of the draw bar, a wedging member OTHER REFERENCES mounted on and carried by the movable second Product En ineerin a es 28, 39, Januar support having opposed inclined sides diverging 1933 g g p g y 

